1. Technical Field of the Invention
The present invention relates to a method and apparatus for controlling consumption current in a computer network, and particularly, to a method and apparatus for controlling consumption current in peripherals connected with a host computer.
2. Description of the Prior Art
Recently, there have been provided new interfaces compatible with plug and play, whereby a personal computer recognizes connections of peripherals to accomplish automatically the system configuration. Thus, circumstances for personal computers have become more and more user-friendly.
In one of these types of new interfaces, for example, such as the universal serial bus (USB), data communication is carried out between a personal computer and peripherals, by using several kinds of data transfer methods including packet communication.
The USB transports various types of packets such as token packet, data packet, and hand-shake packet for carrying out configuration control, guarantee/non-guarantee of data transmission band, guarantee/non-guarantee of real time transfer in isochronous transfer, bulk transfer, or interrupt transfer.
According to the protocol of the USB, the consumption current must not exceed 100 mA under the configuration state, while it must not exceed 100 mA-500 mA under the non-configuration state, depending upon supply capability of the USB. Here, the non-configuration state is defined as the state after finishing the configuration wherein the connected peripherals are ready to work.
For example, a peripheral which requires 50 mA under the configuration state and 300 mA under the non-configuration state had better to control the consumption current, depending upon the states.
Further, there is a peripheral which can detect the accomplishment of the configuration setup in order to control the consumption current.
According to the protocol of the USB, the consumption current must not exceed 100 mA under the configuration state, while it must not exceed 100 mA or 500 mA under the non-configuration state, depending upon supply capability of the USB.
However, the conventional technology has a disadvantage that unnecessary current is consumed by peripherals which consume as much current as consumed during activating an application, after completing the configuration.
Accordingly, batteries are soon exhausted in hand-held computers such as a note personal computer.
Therefore, an object of the present invention is to suppress unnecessary current which is consumed by peripherals which consume as much current as consumed during activating an application.
To solve the above-mentioned problems, the present invention provides a method of controlling the consumption current of the peripherals by adding data for controlling the current, when the peripherals are energized by a host computer. Here, the host computer communicates with the peripherals by using packet transfer.
The present invention also provides a method of controlling the consumption current of the peripherals by adding data for controlling the current, when the peripherals are energized by a host computer, wherein the consumption current is increased during activating an application, while it is decreased during pausing an application
The present invention also provides a method of controlling the consumption current of the peripherals by adding data for controlling the current, when the peripherals which are energized by a host computer communicate with the host computer, through the universal serial bus (USB) interface.
Further, the current consumption is controlled by the transfer of the current control data through the USB.
Further, the current control data may be included in a data packet for SET UP transaction in a communication packet of the USB.
Furthermore, the present invention provides an apparatus for controlling the consumption current of the peripherals, which comprises host computer 1, and peripheral 2 which is energized by the host computer. Here, peripheral 2 exchanges communication data with host computer 1. Further, peripheral 2 farther comprises data detection means for detecting current control data 3 among the data received, and supply control unit 7 for generating supply control signal for variable supply control unit 8 which switches on/off the current supplied for peripheral 2.
Furthermore, the present invention provides an apparatus for controlling the consumption current of the peripherals, which comprises host computer 1, and peripheral 2 which is energized by the host computer. Here, peripheral 2 further comprises communication buffer 4 for communicating with the host computer 1, communication control unit 5 for controlling buffer 4, data detection means for detecting current control data 3 among the data received, supply control unit 7 for generating supply control signal for switching on/off the current on the basis of the output from data detection unit 6, and variable supply control unit 8 for switching on/off the current supplied for peripheral 2 on the basis of the supply control signal.
Further, host computer 1 may be connected with peripheral 2 by USB interface.
According to the method for controlling consumption current of the present invention, the consumption current of the peripherals is controlled by transmitting communication data which is implemented as control data, when the peripherals are energized by a host computer. Here, the host computer is connected with the peripherals through an interface, wherein the implementation of transferred data is freely assigned. The above-mentioned interface treats packets for carrying out configuration process, guarantee/non-guarantee of data transmission band, guarantee/non-guarantee of real time transfer.
Concretely, the present invention relates to a method for controlling the consumption current of the peripherals by using control transfer under the USB interface.
More concretely, host computer 1, and peripheral 2 which is energized by the host computer which exchanges communication data, as shown in FIG. 1, Further, peripheral 2 detects current control data 3 among the data received, and hand over supply control signal for variable supply control unit 8 which switches on/off the current supplied for peripheral 2. Thus, the current consumed by the peripherals becomes completely zero, or minimum.
An effect of the present invention lies in that the consumption current is suppressed in the peripherals which consumes during holding an application as much current as consumed during activating the application. This is because a host computer transmits current control data to its peripherals. Further, the current supply ON/OFF for apart of the circuits which are not required for activating applications is decided by the data communication.
Another effect of the present invention lies in that batteries are not exhausted soon in hand-held computers such as a note personal computer. This is because the supply ON/OFF data is transmitted at the timing synchronized with the star or hold of applications.